This invention relates generally to devices designed to sharpen high speed drill bits. More specifically, the present invention relates to an apparatus for sharpening high speed drill bits of various sizes, which provides inclined grinding surfaces for sharpening not only the face of the drill bit but also the backside of the cutting edge.
As is well known in the art, most high speed drill bits are generally cylindrical and have a pointed leading end. The leading end comprises the drill bit face and provides the cutting edge of the bit. Typically, two helical channels extend the length of the drill bit and at the leading end define "draft" on the drill bit face. Drill bit draft is necessary to conduct cuttings away from the drill site. Without draft a bit would not cut.
Eventually, after a period of use, most drill bits will become dull and require sharpening of the cutting edge. After an extended period of use the cutting edge will actually bend or knurl over towards the backside thereof, reducing the cutting effectiveness of the bit. In order to sharpen the cutting edge of the drill bit face, a small hand-held, rectangular flat diamond sharpener has been utilized. This style of sharpener consists of a small plate-like body having a rectangular diamond-coated plate fastened onto one end. Such sharpeners are utilized in a manner similar to traditional metal files.
The prior hand held sharpener plates suffer the drawback of being sometimes difficult to handle, and have limitations in the manner of use. No provision is made to assure that there will be draft on the drill bit face after sharpening. Further, prior sharpeners provide inadequate access to the inside or backside of the drill bit cutting edge, where the knurling of the cutting edge is found.
Accordingly, there has been a need for a novel drill bit sharpener which operates in a much more advanced and sophisticated manner in comparison with the prior file-like sharpeners. Such an improved sharpener should accommodate manual sharpening of a high speed drill bit and be capable of being hand supported on a flat surface for speed and stability when sharpening bits. Additionally, such a drill bit sharpener should help to ensure that the least amount of metal is removed from the top of the drill bit face during a grinding process to retain adequate draft on the bit surface. Moreover, a novel drill bit sharpener is needed which provides access to the inside or backside of the drill bit cutting edge. The present invention fulfills these needs and provides other related advantages.